Heart scare: Croatia defender Ivan Strinic in action in the World Cup final

Croatian international defender Ivan Strinic has been forced to take a break from football after being diagnosed with a heart condition, his new Serie A club AC Milan revealed on Saturday.

The 31-year-old -- a key member of the Croatian team that reached the World Cup final this summer -- signed a three-year deal with Milan in July but has not yet played for the club.

In a statement the club said that during a routine check-up it was discovered that the player was suffering from a heart problem and would need to take a break.

"During routine medical tests, carried out on all professional athletes in Italy, it was found that Ivan Strinic suffers from the beginnings of hypertrophy in the cardiac muscle which will need further tests following a rest period," the club confirmed in a statement published on Milan's official website.

Strinic was expected to be a key player in AC Milan's title challenge this season alongside other new signings including Gonzalo Higuain, Mattia Caldara, Nikola Kalinic and Pepe Reina.

Strinic, who has 41 caps, played six of Croatia's seven World Cup games in Russia, but the lost the final 4-2 to France.

He started his career with Hadjuk Split in his native Croatia, and also played in France and Ukraine before joining Serie A side Napoli in 2015, and Sampdoria last season.